DASC compositions, process for preparing same and suspensions containing same

ABSTRACT

The present invention provides DASC compositions, which upon introduction into aqueous solutions, form stable, non-gritty suspensions. The present invention also provides stable, non-gritty suspensions comprising the DASC compositions of the present invention admixed in aqueous solutions. In addition, the present invention provides processes for preparing the suspensions which comprise admixing the DASC compositions of the present invention with aqueous solutions. Finally, the present invention provides processes for preparing the DASC compositions of the present invention.

This is a continuation of application Ser. No. 08/824,509, filed Mar.26, 1997, the contents of which is hereby incorporated by reference inits entirety.

FIELD OF THE INVENTION

The present invention is directed to improved dihydroxy aluminum sodiumcarbonate (DASC) compositions, which unlike prior art DASC, form stable,non-gritty suspensions in aqueous solutions. The improved properties ofthe DASC compositions of the present invention render the compositionsparticularly useful as components of liquid antacids, and other consumerand industrial products, for which stable, non-gritty suspensions aredesirable.

BACKGROUND OF THE INVENTION

DASC is a known aluminum salt which exhibits excellent acid neutralizingcapacity, and therefore is particularly useful in antacid formulations.(See, Grote, U.S. Pat. No. 2,783,179, issued Feb. 26, 1957). However,the use of prior art DASC as the active ingredient in antacidformulations has been generally limited to non-liquid formulations (e.g.Rolaid tablets) because prior art DASC does not form stable aqueoussuspensions at concentrations that produce acceptable acid neutralizingcapacity. In addition, even dilute suspensions of prior art DASC possessan undesirable gritty appearance and taste, and rapidly form a sedimentlayer.

Several attempts have been made to stabilize aluminum hydroxidesuspensions. For example, Alford, U.S. Pat. No. 2,999,790, issued Sep.12, 1961, described combining hexitols such as sorbitol and mannitolwith aluminum hydroxide gels in water to prevent thickening andhardening of the aluminum hydroxide gels.

Greene, et al., U.S. Pat. No. 3,591,680, issued Jul. 6, 1971, describedthe use of hydroxypropyl cellulose for stabilizing antacids such asmagnesium carbonate, magnesium hydroxide, aluminum hydroxide, or calciumcarbonate, which essentially involved slurrying the dry actives withwater and hydroxypropyl cellulose.

Schmank, U.S. Pat. No. 3,629,229, issued Dec. 21, 1971, described watersoluble antacid formulations that were prepared by reacting aluminumpowder or aluminum isopropoxide with polyhydroxyl hydrocarbons.

Rubino, et al., U.S. Pat. No. 4,112,072, issued Sep. 5, 1978, describedantacid compositions that were prepared by codrying hydrous, gelatinousaluminum-hydroxide materials with di- or trihydroxy alcohols.

Beekman, U.S. Pat. No. 3,272,704, issued Sep. 13, 1966, describedantacid compositions that were prepared by co-drying aluminum hydroxideand magnesium hydroxide gels with hexitols.

Hem, et al., U.S. Pat. No. 3,911,090, issued Oct. 7, 1995, describedantacid compositions containing silicate anions and aluminum hydroxycarbonates which purportedly possess the antacid properties of liquidaluminum hydroxide gels.

However, prior to the present invention, no methods have been taught orsuggested for preparing DASC compositions which, upon introduction intoaqueous solutions, results in suspensions that have the desiredproperties of stability and non-grittiness.

SUMMARY OF THE INVENTION

The present invention is based upon the discovery by the inventors ofDASC compositions, which unlike prior art DASC, form stable, non-grittysuspensions in aqueous solutions. The DASC compositions of the presentinvention, unlike prior art DASC, also can be formulated so that uponintroduction into aqueous solutions, the resulting suspensions not onlypossess the aforementioned desired physical properties, but also haveacceptable acid neutralizing capacities. Accordingly, the DASCcompositions of the present invention are particularly desirable for usein liquid antacid formulations.

In addition to stability and non-grittiness, the DASC compositions ofthe present invention also can be formulated to have gelling and/ortranslucent properties. Accordingly, the DASC compositions of thepresent invention are also suitable for use as components of otherconsumer or industrial products such as tooth pastes, soaps, detergents,pharmaceuticals, lotions, nutriceuticals, plastic additives, chemicalfoaming agents, acid scavengers, gellants, cleaners, and the like, forwhich stable and non-gritty, and/or gelling and/or translucentproperties are desirable.

The properties of the DASC compositions of the present invention relateto the manner in which the compositions are prepared. Specifically, ithas been found that if DASC is synthesized under certain temperatureconditions, then the resulting dried DASC composition, whenreconstituted in an aqueous solution, results in a suspension having thedesired properties. It also has been found that if at least one polyolis included in freshly synthesized DASC before drying, or is includedduring the reaction of DASC, then the resulting co-dried DASC/polyolcomposition, when reconstituted in an aqueous solution, will also resultin a suspension that possesses the desired properties of stability andnon-grittiness. In addition, depending upon the choice of polyol, thesuspensions also may be prepared to be translucent and/or gelling.Accordingly, in addition to the improved DASC compositions andsuspensions containing the same, the present invention also providesprocesses for preparing the DASC compositions of the present invention.

Additional objects of the invention will be apparent from thedescription which follows.

DETAILED DESCRIPTION OF THE INVENTION

The composition of the present invention is directed to a powder thatcomprises DASC, which upon introduction into an aqueous solution, formsa stable, non-gritty suspension. As used herein, "stable" means that thepowder does not settle or separate in the suspension but rather stays insolution resulting in a suspension having a homogeneous appearance. Thisstability lasts for at least three months, preferably at least sixmonths, and most preferably for up to a year or more. "Non-gritty" meansthat the suspension has only minor or no grittiness.

The powder of the present invention also can include at least onepolyol. Suitable polyols include but are not limited to sorbitol,glycerin, mannitol, maltodextrin, pentaerythritol, fructose, glucose andsucralose. However, as discussed in the Examples below, the inventors ofthe present invention have found that polyols such as propylene glycol,1,3-butylene glycol, neopentyl glycol, polyethylene glycol and sodiumcarboxymethylcellulose do not result in suspensions having the desiredstability and non-gritty properties. Accordingly, such polyols are notincluded within the term "polyols" as used herein. The ratio ofDASC:polyol to arrive at the desired properties may vary. However, inthe preferred embodiment, the weight ratio of DASC:polyol is 0.67:1 to19:1 (40-95% DASC), and more preferably is 1.5:1 to 5:1 (60-83% DASC).

The DASC powder of the present invention is prepared by reacting anorganoaluminum compound with a carbonate in an aqueous solution at atemperature of between about -20° C. and about 10° C. The molar ratio oforganoaluminum compound:carbonate is preferably 1:1 to 1:3. Sodiumchloride or isopropyl alcohol also may be added to the reaction mixture.Suitable organoaluminum compounds include aluminum alkoxides such asaluminum iso-propoxide, aluminum ethoxide and aluminum sec-butoxide.Preferably, the organoaluminum compound is aluminum iso-propoxide. Theinventors of the present invention have found that the use of aluminumchloride or sodium aluminate does not result in a suspension having thedesired properties. Accordingly, aluminum chloride and sodium aluminateare not included within the term "organoaluminum compound" as usedherein. The carbonate includes but is not limited to sodium bicarbonateand sodium carbonate, but is preferably sodium bicarbonate.

After the DASC is prepared using the above process, it is isolated bymethods known in the art such as filtration, centrifugation, settling,decanting or a combination thereof. For batch preparations, filtrationis preferred. The DASC may then be washed with water following isolationto remove isopropyl alcohol formed during the reaction. The isolatedDASC is then dried into powder form by suitable methods including butnot limited to air-drying, oven-drying, fan-drying, spray-drying or acombination thereof.

When at least one polyol is included in the powder with DASC, it hasbeen found that the desired DASC/polyol powder can be prepared bycertain modifications to the above process. Specifically, the polyol(s)can be added directly to the freshly prepared wet DASC before or afterthe isolation step, or can be combined with the organoaluminum compoundand the carbonate reactants before DASC is formed. However, it ispreferred that the polyol is added after DASC has been isolated since ithas been found that when the polyol is combined with DASC or thereactants before isolation of DASC, some of the polyol may be lost inthe isolation step. The inventors also have found that dry DASC cannotbe combined with the polyol in water and result in an aqueousDASC/polyol suspension having the desired properties. Accordingly, theuse of previously prepared dry DASC is not encompassed by the processesof the present invention.

The organoaluminum compound and carbonate used in preparing theDASC/polyol powder are the same as described above for the DASC powder,with aluminum iso-propoxide and sodium bicarbonate being the preferredreactants. However, the reaction can be performed at a broadertemperature of between about -20° C. and about 120° C. For the sake ofease, the reaction is preferably performed at room temperature. Suitablepolyols again include but are not limited to sorbitol, glycerin,mannitol, maltodextrin, pentaerythritol, fructose, glucose andsucralose. However, hexitols such as sorbitol and mannitol arepreferred.

The present invention also provides a stable, non-gritty suspensioncomprising either the DASC powder or the DASC/polyol powder of thepresent invention. The suspension may be prepared by admixing the powderwith an aqueous solution at a w/w that results in the suspension havingthe desired physical properties. The inventors of the present inventionhave found that at a w/w of 1-15%, preferably at a w/w of 1-10%, andmost preferably at a w/w of 2-6%, the suspension will be stable andnon-gritty. However, it is within the confines of the present inventionthat higher or lower concentrations of the powder may be utilized ifthey result in a suspension having the desired properties.

The present inventors also have found that the suspensions of thepresent invention, depending upon the choice and concentration of polyolin the DASC/polyol powder, also possess other desirable properties inaddition to stability and non-grittiness. For example, it has been foundthat the use of sorbitol, glycerin, mannitol, maltodextrin,pentaerythritol and fructose as the polyol can result in a suspensionthat not only is stable and non-gritty, but also is translucent. As usedherein, "translucent" means that the suspension is not opaque such thatlight can pass through the suspension in a manner that permits theoutline of objects (although not the details of such objects) to be seenthrough the suspension. In addition, it has been found that the use ofpolyols such as mannitol or fructose, for example, can result in asuspension that also has gelling properties.

Based upon the aforementioned properties, the powders or suspensions ofthe present invention are useful as components of various consumer orindustrial products for which such properties are desirable. Suchproducts include but are not limited to liquid antacids, tooth pastes,soaps, detergents, pharmaceuticals, lotions, nutriceuticals, plasticadditives, chemical foaming agents, acid scavengers, gellants, cleaners,and the like. The formulation of such products with the powders andsuspensions of the present invention are well within the purview ofthose skilled in the art.

However, because the suspensions are stable and non-gritty, and can beformulated to have an acceptable acid neutralizing capacity, thesuspensions of the present invention are preferably used as the activeingredient in liquid antacid formulations. In this connection, it ispreferred that the suspensions of the present invention have an acidneutralizing capacity (ANC) of 0.1-3.0, and more preferably an ANC of0.5-1.0. However, higher or lower ANC values can be obtained if desired.The ANC can be determined using the procedures outlined in the U.S.Pharmacopoeia. In addition to the stability and non-gritty properties,the antacids can also be formulated to have gelling and/or translucentproperties, as described above. In the particularly preferredembodiment, the liquid antacids are translucent, stable, non-gritty andnon-gelling. Liquid antacids having these properties can be prepared asdescribed in the examples below using polyols such as such sorbitol,glycerin, mannitol, maltodextrin, pentaerythritol and fructose. Finally,it is within the confines of the present invention that the liquidantacid formulations may be combined with flavoring agents, coloringagents, preservatives, and the like, if so desired.

The present invention is described in the following examples which areset forth to aid in the understanding of the invention, and should notbe construed to limit in any way the invention as defined in the claimswhich follow thereafter.

EXAMPLE 1 Dry DASC And Water

A 5% (w/w) aqueous suspension of dry DASC, previously preparedessentially as described in Example 1 of U.S. Pat. No. 2,783,179, wasstirred for about 30 minutes with gentle heating in order to ensurecomplete dispersion. The results are summarized in Table 1, and are asfollows: ANC, not determined; Appearance, opaque; Stability, badsettling; Grittiness, bad; Evaluation, unacceptable.

EXAMPLE 2 DASC(Cold) Only/Salt Solution

97.9 g of sodium bicarbonate were added to 440 g of salt solutioncontaining 40 g of sodium chloride and 400 g of ice, and cooled to -13°C. 204 g (1 mole) of aluminum iso-propoxide were then added to themixture and stirred for 1 hour. The resulting precipitate was isolatedby vacuum filtration, air dried, and then oven dried at 100° C.overnight. A 5% (w/w) aqueous suspension of the material was thenprepared, and stirred for about 30 minutes with gentle heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 1.265; Appearance, semi-opaque; Stability,excellent; Grittiness, none; Evaluation, acceptable.

EXAMPLE 3 DASC(Cold) Only

146.9 g (1.75 moles) of sodium bicarbonate and 60 g isopropyl alcoholwere added to 540 g of ice water, and cooled to -10° C. with dry ice.306 g (1.5 moles) of aluminum iso-propoxide were then added to themixture. The resulting precipitate was isolated by vacuum filtration,air dried, and then oven dried overnight. A 5% (w/w) aqueous suspensionof the material was then prepared, and stirred for about 30 minutes withgentle heating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 1.065; Appearance,semi-opaque; Stability, excellent; Grittiness, none; Evaluation,acceptable.

EXAMPLE 4 Dry DASC(Room Temp.) And Sorbitol

Dry DASC, previously prepared essentially as described in Example 1 ofU.S. Pat. No. 2,783,179, was reslurried with enough sorbitol to give asorbitol/Al₂ O₃ ratio of approximately 1:1. The slurry was air dried,and then oven dried at 100° C. overnight. A 5% (w/w) aqueous suspensionof the material then was prepared, and stirred for about 30 minutes withgentle heating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 0.920; Appearance,opaque; Stability, bad settling; Grittiness, bad; Evaluation,unacceptable.

EXAMPLE 5 DASC(Hot); Sorbitol Before Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum isopropoxide, heated to 100° C., then wereadded to the mixture and stirred for 1 hour. 128 g of a 70% sorbitolsolution (90 g of 100% sorbitol and 38 g of water) then were added tothe mixture, and stirred for 1 hour. The resulting precipitate wasisolated by vacuum filtration, air dried, and then oven dried at 100° C.overnight. More than 50% of the sorbitol was lost in the filtrationprocess. A 5% (w/w) aqueous suspension of the material then wasprepared, and stirred for about 30 minutes with gentle heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 0.947; Appearance, translucent; Stability,excellent; Grittiness, none; Evaluation, preferred.

EXAMPLE 6 Sodium Bicarbonate/Sorbitol/AIP(Hot)

147 g (1.75 moles) of sodium bicarbonate, 540 g of water, and 390 g of a70% sorbitol solution (i.e. 273 g of 100% sorbitol and 170 g of water)were mixed. 306 g (1.5 moles) of aluminum iso-propoxide, heated to 100°C., then were added to the mixture and stirred for 2 hours. Theresulting precipitate was isolated by vacuum filtration. Roughly halfthe batch filtered rather well. The filtered liquid and unfiltered solidwere recombined to prevent loss of sorbitol, air dried, and then ovendried at 100° C. overnight. A 5% (w/w) aqueous suspension of thematerial then was prepared, and stirred for about 30 minutes with gentleheating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 0.677; Appearance,translucent; Stability, excellent; Grittiness, none; Evaluation,acceptable.

EXAMPLE 7 DASC(Cold); 70% Sorbitol After Filtration

146.9 g (1.75 moles) of sodium bicarbonate and 60 g isopropyl alcoholwere added to 540 g of ice water, and cooled to -10° C. with dry ice.306 g (1.5 moles) of aluminum iso-propoxide then were added to themixture and stirred. The resulting precipitate was isolated by vacuumfiltration and reslurried with 128 g of a 70% sorbitol solution (i.e. 90g of 100% sorbitol and 38 g of water). After mixing, the resultingmixture was air dried, and then oven dried at 100° C. overnight. A 5%(w/w) aqueous suspension of the material then was prepared, and stirredfor about 30 minutes with gentle heating in order to ensure completedispersion. The results are summarized in Table 1, and are as follows:ANC, 0.925; Appearance, translucent; Stability, excellent; Grittiness,none; Evaluation, preferred.

EXAMPLE 8 DASC(Room Temp); 70% Sorbitol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water atroom temperature. 306 g (1.5 moles) of aluminum iso-propoxide then wereadded to the mixture and stirred. The resulting precipitate was isolatedby vacuum filtration, and then reslurried with 128 g of a 70% sorbitolsolution (i.e. 90 g of 100% sorbitol and 38 g of water). After mixing,the resulting mixture was air dried, and then oven dried at 100° C.overnight. A 5% (w/w) aqueous suspension of the material then wasprepared, and stirred for about 30 minutes with gentle heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 0.910; Appearance, translucent; Stability,excellent; Grittiness, none; Evaluation, preferred.

EXAMPLE 9 DASC(Hot); 70% Sorbitol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water,and heated to 60-70° C. 306 g (1.5 moles) of aluminum iso-propoxide thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with128 g of a 70% sorbitol solution (i.e. 90 g of 100% sorbitol and 38 g ofwater). After mixing, the resulting mixture was air dried, and then ovendried at 100° C. overnight. A 5% (w/w) aqueous suspension of thematerial then was prepared, and stirred for about 30 minutes with gentleheating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, not determined;Appearance, translucent; Stability, excellent; Grittiness, none;Evaluation, acceptable.

EXAMPLE 10 DASC(Hot); 50% Sorbitol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to about 100° C.,then were added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with180 g of a 50% sorbitol solution (i.e. 90 g of 100% sorbitol and 90 g ofwater). After mixing for 1 hour, the resulting mixture was air dried,and then oven dried at 100° C. overnight. A 5% (w/w) aqueous suspensionof the material then was prepared, and stirred for about 30 minutes withgentle heating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 0.905; Appearance,translucent; Stability, excellent; Grittiness, none; Evaluation,preferred.

EXAMPLE 11 DASC(Hot); 30% Sorbitol After filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with300 g of a 30% sorbitol solution (i.e. 90 g of 100% sorbitol and 210 gof water). After mixing for 1 hour, the resulting mixture was air dried,and then oven dried at 100° C. overnight. A 5% (w/w) aqueous suspensionof the material then was prepared, and stirred for about 30 minutes withgentle heating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 0.990; Appearance,translucent; Stability, excellent; Grittiness, none; Evaluation,preferred.

EXAMPLE 12 DASC(Hot): 10% Sorbitol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with51 g of a 70% sorbitol solution (i.e. 36 g of 100% sorbitol and 15 g ofwater). After mixing for 1 hour, the resulting mixture was air dried,and then oven dried at 100° C. overnight. A 5% (w/w) aqueous suspensionof the material then was prepared, and stirred for about 30 minutes withgentle heating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 1.159; Appearance,translucent; Stability, excellent; Grittiness, none; Evaluation,preferred.

EXAMPLE 13 DASC(Hot); 5% Sorbitol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with26 g of a 70% sorbitol solution (i.e. 18 g of 100% sorbitol and 8 g ofwater). After mixing for 1 hour, the resulting mixture was air dried,and then oven dried at 100° C. overnight. A 5% (w/w) aqueous suspensionof the material then was prepared, and stirred for about 30 minutes withgentle heating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 1.109; Appearance,semi-translucent; Stability, excellent; Grittiness, minor; Evaluation,acceptable.

EXAMPLE 14 DASC(Hot); Glycerin After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with90 g of glycerin and enough water to form a homogeneous slurry. Aftermixing for 1 hour, the resulting mixture was air dried, and then ovendried at 100° C. overnight. A 5% (w/w) aqueous suspension of thematerial then was prepared, and stirred for about 30 minutes with gentleheating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 0.926; Appearance,semi-translucent; Stability, excellent; Grittiness, none; Evaluation,acceptable.

EXAMPLE 15 DASC(Room Temp.); 50% Glycerin After Filtration

295.6 g (3.53 moles) of sodium bicarbonate were added to 2400 g ofwater. 629 g (3.1 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakethen was added to a mixture of 46 g of glycerin dissolved in 700 g ofwater. After stirring for 10 minutes, the resulting mixture was fandried, and then oven dried at 105-110° C. overnight. A 5% (w/w) aqueoussuspension of the material then was prepared, and stirred for about 30minutes with gentle heating in order to ensure complete dispersion. Theresults are summarized in Table 1, and are as follows: ANC, 1.158;Appearance, opaque; Stability, excellent; Grittiness, none; Evaluation,unacceptable for liquid antacids (acceptable for gelled antacids).

EXAMPLE 16 DASC(Hot); Mannitol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with90 g of mannitol dissolved in 495 g of water. After mixing for 1 hour,the resulting mixture was air dried, and then oven dried at 100° C.overnight. A 5% (w/w) aqueous suspension of the material then wasprepared, and stirred for about 30 minutes with gently heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 1.150; Appearance, translucent; Stability,excellent; Grittiness, none; Evaluation, preferred.

EXAMPLE 17 DASC(Room Temp.): 50% Mannitol After Filtration

287.6 g (3.42 moles) of sodium bicarbonate were added to 2400 g ofwater. 612 g (3.0 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakewas then added to a mixture of 44.8 g of mannitol dissolved in 1000 g ofwater. After stirring for 10 minutes, the resulting mixture was fandried, and then oven dried at 105-110° C. overnight. A 5% (w/w) aqueoussuspension of the material then was prepared, and stirred for about 30minutes with gentle heating in order to ensure complete dispersion. Theresults are summarized in Table 1, and are as follows: ANC, 1.067;Appearance, semi-translucent; Stability, excellent; Grittiness, minor;Evaluation, unacceptable for liquid antacids (acceptable for gelledantacids).

EXAMPLE 18 DASC(Room Temp.); Inositol After Filtration

287.6 g (3.42 moles) of sodium bicarbonate were added to 2400 g ofwater. 612 g (3.0 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakewas then added to a mixture of 89.6 g of inositol dissolved in 900 g ofwater. After stirring for 10 minutes, the resulting mixture was fandried, and then oven dried at 105°-110° C. overnight. A 5% (w/w) aqueoussuspension of the material then was prepared, and stirred for about 30minutes with gentle heating in order to ensure complete dispersion. Theresults are summarized in Table 1, and are as follows: ANC, 0.809;Appearance, semi-opaque; Stability, some settling; Grittiness, bad;Evaluation, unacceptable.

EXAMPLE 19 DASC(Room Temp.); 50% Inositol After Filtration

287.6 g (3.42 moles) of sodium bicarbonate were added to 2400 g ofwater. 612 g (3.0 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakewas then added to a mixture of 44.8 g of inositol dissolved in 700 g ofwater. After stirring for 10 minutes, the resulting mixture was fandried, and then oven dried at 105°-110° C. overnight. A 5% (w/w) aqueoussuspension of the material then was prepared, and stirred for about 30minutes with gentle heating in order to ensure complete dispersion. Theresults are summarized in Table 1, and are as follows: ANC, 1.025;Appearance, opaque; Stability, separated; Grittiness, none; Evaluation,unacceptable.

EXAMPLE 20 DASC(Hot); Pentaerythritol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with90 g of pentaerythritol dissolved in 270 g of warm water. After mixingfor 1 hour, the resulting mixture was air dried, and then oven dried at100° C. overnight. A 5% (w/w) aqueous suspension of the material thenwas prepared, and stirred for about 30 minutes with gentle heating inorder to ensure complete dispersion. The results are summarized in Table1, and are as follows: ANC, 0.885; Appearance, translucent; Stability,excellent; Grittiness, none; Evaluation, preferred.

EXAMPLE 21 DASC(Room Temp.); 50% Pentaerythritol After Filtration

287.6 g (3.42 moles) of sodium bicarbonate were added to 2400 g ofwater. 615 g (3.0 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakewas then added to a mixture of 44.8 g of pentaerythritol dissolved in700 g of water. After stirring for 10 minutes, the resulting mixture wasfan dried, and then oven dried at 105°110° C. overnight. A 5% (w/w)aqueous suspension of the material then was prepared, and stirred forabout 30 minutes with gentle heating in order to ensure completedispersion. The results are summarized in Table 1, and are as follows:ANC, 1.077; Appearance, translucent; Stability, separated; Grittiness,none; Evaluation, unacceptable.

EXAMPLE 22 DASC(Hot); Sucrose After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with90 g of sucrose dissolved in 38 g of water. After mixing for 1 hour, theresulting mixture was air dried, and then oven dried at 100° C.overnight. A 5% (w/w) aqueous suspension of the material then wasprepared, and stirred for about 30 minutes with gentle heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 0.945; Appearance, semi-opaque; Stability, badsettling; Grittiness, bad; Evaluation, unacceptable.

EXAMPLE 23 DASC(Hot); Maltodextrin After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with90 g of maltodextrin dissolved in 38 g of water. After mixing for 1hour, the resulting mixture was air dried, and then oven dried at 100°C. overnight. A 5% (w/w) aqueous suspension of the material then wasprepared, and stirred for about 30 minutes with gentle heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 0.885; Appearance, translucent; Stability,excellent; Grittiness, none; Evaluation, preferred.

EXAMPLE 24 DASC(Room Temp.); Acacia After Filtration

287.6 g (3.42 moles) of sodium bicarbonate were added to 2400 g ofwater. 612 g (3.0 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakewas then added to a mixture of 89.6 g of acacia dissolved in 900 g ofwater. After stirring for 10 minutes, the resulting mixture was fandried, and then oven dried at 105-110° C. overnight. A 5% (w/w) aqueoussuspension of the material then was prepared, and stirred for about 30minutes with gentle heating in order to ensure complete dispersion. Theresults are summarized in Table 1, and are as follows: ANC, 0.853;Appearance, opaque; Stability, bad settling; Grittiness, bad;Evaluation, unacceptable.

EXAMPLE 25 DASC(Room Temp.); Fructose After Filtration

287.6 g (3.42 moles) of sodium bicarbonate were added to 2400 g ofwater. 617 g (3.0 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakewas then added to a mixture of 89.6 g of fructose dissolved in 700 g ofwater. After stirring for 10 minutes, the resulting mixture was fandried, and then oven dried at 105-110° C. overnight. A 5% (w/w) aqueoussuspension of the material then was prepared, and stirred for about 30minutes with gentle heating in order to ensure complete dispersion. Theresults are summarized in Table 1, and are as follows: ANC, 0.920;Appearance, translucent; Stability, excellent; Grittiness, none;Evaluation, preferred.

EXAMPLE 26 DASC(Hot); Propylene Glycol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with90 g of propylene glycol and enough water to form a homogeneous slurry.After mixing for 1 hour, the resulting mixture was air dried, and thenoven dried at 100° C. overnight. A 5% (w/w) aqueous suspension of thematerial then was prepared, and stirred for about 30 minutes with gentleheating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 0.970; Appearance,semi-opaque; Stability, minor settling; Grittiness, bad; Evaluation,unacceptable.

EXAMPLE 27 DASC(Hot); 1,3-Butylene Glycol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with90 g of 1,3-butylene glycol and enough water to form a homogeneousslurry. After mixing for 1 hour, the resulting mixture was air dried,and then oven dried at 100° C. overnight. A 5% (w/w) aqueous suspensionof the material then was prepared, and stirred for about 30 minutes withgentle heating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, 0.992; Appearance,opaque; Stability, bad settling; Grittiness, bad; Evaluation,unacceptable.

EXAMPLE 28 DASC(Hot); Neopentyl Glycol After Filtration

147 g (1.75 moles) of sodium bicarbonate were added to 540 g of water.306 g (1.5 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with90 g of neopentyl glycol dissolved in 38 g of water. After mixing for 1hour, the resulting mixture was air dried, and then oven dried at 100°C. overnight. A 5% (w/w) aqueous suspension of the material then wasprepared, and stirred for about 30 minutes with gentle heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 1.005; Appearance, opaque; Stability, badsettling; Grittiness, bad; Evaluation, unacceptable.

EXAMPLE 29 DASC(Room Temp.); PEG (200 MW) After Filtration

287.6 g (3.42 moles) of sodium bicarbonate were added to 2400 g ofwater. 612 g (3.0 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakethen was added to a mixture of 89.6 g of polyethylene glycol (200 MW)dissolved in 700 g of water. After stirring for 10 minutes, theresulting mixture was fan dried, and then oven dried at 105-110° C.overnight. A 5% (w/w) aqueous suspension of the material then wasprepared, and stirred for about 30 minutes with gentle heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 0.820; Appearance, opaque; Stability,separated; Grittiness, bad; Evaluation, unacceptable.

EXAMPLE 30 DASC(Room Temp.); PEG (1500 MW) After Filtration

287.6 g (3.42 moles) of sodium bicarbonate were added to 2400 g ofwater. 612 g (3.0 moles) of aluminum iso-propoxide then were added tothe mixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakewas then added to a mixture of 89.6 g of polyethylene glycol (1500 MW)dissolved in 700 g of water. After stirring for 10 minutes, theresulting mixture was fan dried, and then oven dried at 105-110° C.overnight. A 5% (w/w) aqueous suspension of the material then wasprepared, and stirred for about 30 minutes with gentle heating in orderto ensure complete dispersion. The results are summarized in Table 1,and are as follows: ANC, 0.869; Appearance, opaque; Stability, badsettling; Grittiness, bad; Evaluation, unacceptable.

EXAMPLE 31 DASC(Hot); Sodium Carboxymethylcellulose After Filtration

49 g (0.58 moles) of sodium bicarbonate were added to 180 g of water.102 g (0.50 moles) of aluminum iso-propoxide, heated to 100° C., thenwere added to the mixture and stirred for 1 hour. The resultingprecipitate was isolated by vacuum filtration, and then reslurried with30 g of sodium carboxymethylcellulose dispersed in 200 g of water. Aftermixing for 1 hour, the resulting mixture was air dried, and then ovendried at 100° C. overnight. A 5% (w/w) aqueous suspension of thematerial then was prepared, and stirred for about 30 minutes with gentleheating in order to ensure complete dispersion. The results aresummarized in Table 1, and are as follows: ANC, not determined;Appearance, opaque; Stability, solidified; Grittiness, bad; Evaluation,unacceptable.

EXAMPLE 32 Replace AIP With ASB; Sorbitol After Filtration

143.7 g (1.7 moles) of sodium bicarbonate were added to 2000 g of water.364.6 g (1.5 moles) of aluminum sec-butoxide then were added to themixture and stirred for 1 hour at room temperature. The resultingprecipitate was isolated by vacuum filtration. 50% of the filter cakewas then added to 64 g of a 70% sorbitol solution (i.e. 45 g of 100%sorbitol and 19 g of water) dissolved in 350 g of water. After stirringfor 10 minutes, the resulting mixture was fan dried, and then oven driedat 105°110° C. overnight. A 5% (w/w) aqueous suspension of the materialthen was prepared, and stirred for about 30 minutes with gentle heatingin order to ensure complete dispersion. The results are summarized inTable 1, and are as follows: ANC, 0.964; Appearance, translucent;Stability, excellent; Grittiness, minor; Evaluation, acceptable.

                  TABLE 1                                                         ______________________________________                                        Ex.  ANC     Appearance  Stability                                                                             Grit. Evaluation*                            ______________________________________                                         1   N.D.    opaque      bad settl.                                                                            bad   unacceptable                            2   1.265   semi-opaque excellent                                                                             none  acceptable                              3   1.065   semi-opaque excellent                                                                             none  acceptable                              4   0.920   opaque      bad settl.                                                                            bad   unacceptable                            5   0.947   translucent excellent                                                                             none  preferred                               6   0.677   translucent excellent                                                                             none  acceptable                              7   0.925   translucent excellent                                                                             none  preferred                               8   0.910   translucent excellent                                                                             none  preferred                               9   N.D.    translucent excellent                                                                             none  acceptable                             10   0.905   translucent excellent                                                                             none  preferred                              11   0.990   translucent excellent                                                                             none  preferred                              12   1.159   translucent excellent                                                                             none  preferred                              13   1.109   translucent excellent                                                                             minor acceptable                             14   0.926   semi-trans. excellent                                                                             none  acceptable                             15   1.158   opaque      excellent                                                                             none  unacceptable                           16   1.150   translucent excellent                                                                             none  preferred                              17   1.067   semi-trans. excellent                                                                             minor unacceptable                           18   0.809   semi-opaque some settl.                                                                           bad   unacceptable                           19   1.025   opaque      separated                                                                             none  unacceptable                           20   0.885   translucent excellent                                                                             none  preferred                              21   1.077   translucent separated                                                                             none  unacceptable                           22   0.945   semi-opaque bad settl.                                                                            bad   unacceptable                           23   0.885   translucent excellent                                                                             none  preferred                              24   0.853   opaque      bad settl.                                                                            bad   unacceptable                           25   0.920   translucent excellent                                                                             none  preferred                              26   0.970   semi-opaque minor settl.                                                                          bad   unacceptable                           27   0.992   opaque      bad settl.                                                                            bad   unacceptable                           28   1.005   opaque      bad settl.                                                                            bad   unacceptable                           29   0.820   opaque      separated                                                                             bad   unacceptable                           30   0.869   opaque      bad settl.                                                                            bad   unacceptable                           31   N.D.    opaque      solidified                                                                            bad   unacceptable                           32   0.964   translucent excellent                                                                             minor acceptable                             ______________________________________                                    

*Evaluation based upon preferred suspensions for use in liquid antacidformulations. The preferred criteria were met by those suspensionshaving an ANC>0.8 (mEq of acid consumed per gram of suspension tested,as determined using Method 301 of USP23), translucent appearance,excellent stability and no grittiness. Examples 15 and 17, althoughunacceptable for liquid antacids, are acceptable for gelled antacids.

All issued U.S. patents mentioned hereinabove are hereby incorporated byreference in their entirety.

While the foregoing invention has been described in some detail forpurposes of clarity and understanding, it will be appreciated by oneskilled in the art from a reading of the disclosure that various changesin form and detail can be made without departing from the true scope ofthe invention in the appended claims.

What is claimed:
 1. A process for preparing a dihydroxy aluminum sodiumcarbonate (DASC)/polyol powder comprising the steps of: (i) synthesizingDASC; (ii) isolating the synthesized DASC to provide isolated, undriedDASC; (iii) mixing the isolated, undried DASC with water and at leastone polyol selected from the group consisting of sorbitol, glycerin,mannitol, maltodextrin and fructose to form an aqueous DASC/polyolsuspension; and (iv) drying the aqueous DASC/polyol suspension to form aDASC/polyol powder.
 2. The process of claim 1, wherein DASC issynthesized by reacting an organoaluminum compound with a carbonate inan aqueous solution.
 3. The process of claim 2, wherein the molar ratioof organoaluminum compound:carbonate is 1:1 to 1:3.
 4. The process ofclaim 2, wherein the organoaluminum compound and the carbonate arereacted at a temperature of -20° C. to 120° C.
 5. The process of claim2, wherein the organoaluminum compound and the carbonate are reacted atroom temperature.
 6. The process of claim 2, wherein the organoaluminumcompound is an aluminum alkoxide.
 7. The process of claim 6, wherein thealuminum alkoxide is aluminum iso-propoxide, aluminum ethoxide oraluminum sec-butoxide.
 8. The process of claim 7, wherein the aluminumalkoxide is aluminum iso-propoxide.
 9. The process of claim 2, whereinthe carbonate is sodium bicarbonate or sodium carbonate.
 10. The processof claim 9, wherein the carbonate is sodium bicarbonate.
 11. The processof claim 2, wherein the organoaluminum compound is aluminumiso-propoxide and the carbonate is sodium bicarbonate.
 12. The processof claim 1, wherein the synthesized DASC is isolated by filtration,centrifugation, settling, decanting or a combination thereof.
 13. Theprocess of claim 1, wherein the isolated, undried DASC is washed withwater before being mixed with the aqueous polyol.
 14. The process ofclaim 1, wherein the weight ratio of DASC:polyol in step (iii) is 0.67:1to 19:1.
 15. The process of claim 1, wherein the weight ratio ofDASC:polyol in step (iii) is 1.5:1 to 5:1.
 16. The process of claim 1,wherein the polyol is sorbitol.
 17. The process of claim 1, wherein theaqueous DASC/polyol suspension is dried by air-drying, oven-drying,fan-drying, spray-drying, or a combination thereof.